1. Field of the Invention
The present invention relates to an air filter leak inspection method, more particularly relates to an air filter leak inspection method having high inspection efficiency, good accuracy and can avoid equipment damage.
2. Description of Related Art
With the progress in human industrial technology, air cleanness poses a significant impact on fabrication process, environmental safety and equipment in many new types of the laboratories, hospitals and the factories, even the suspended particles with 0.5 μm/ft3 of the air in some environment are required to be lower than 1. In order to obtain the air with high cleanness, air filter of HEPA (High Efficiency Particulate Air, HEPA) or ULPA (Ultra-Low Particulate Air, ULPA) is needed to filter the outside air. However, if the air filter with high efficiency leaks in the fabrication process, the air filter will lose its original filtering capability, thereby causing critical effects to the fabrication process, environmental safety and equipment. Therefore, in order to improve the reliability of the air filter, it is needed to inspect whether the air filter leaks or not.
U.S. Pat. No. 4,494,403 discloses an air filter leak inspection method, wherein the probe traverses across one side of the air filter to inspect the air filter. However, when performing the air filter leak inspection, the probe in moving may go beyond the range of the air filter with the difference of the size of the air filter to be inspected and the number of the probes to be used. Hence, the probe can't be effectively used to perform the inspection, more than that, the probe may hit the frame for fixing the air filter or baffle plate so as to cause equipment damage. Therefore, there still needs improvement in the conventional air filter leak inspection method.